Structural elucidation studies of 15-membered azalide macrocycles using H/D exchange and ESI-MS(n.)

J Pharm Biomed Anal. 2013 Dec:86:1-10. doi: 10.1016/j.jpba.2013.07.011. Epub 2013 Aug 2.

Abstract

A comprehensive study of fragmentation pathways of 15-membered azalide macrocycles using electrospray ionisation with multistage mass spectrometry (ESI-MS(n)) is presented in this work. Hydrogen/deuterium (H/D) exchange experiments and high-resolution mass spectrometry were used to investigate the proposed fragmentation pathways. In addition, the fragmentation patterns of sodium adduct ions [M+Na](+) of the macrocycles were also investigated as the presence of an alkali metal interacting with the aglycone ring influences the product-ion spectra.

Keywords: 15-Membered azalide aglycone; ESI-MS(n); Fragmentation; H/D Exchange; Macrolides; Sodium adducts.

MeSH terms

  • Azithromycin / analysis
  • Azithromycin / chemistry
  • Deuterium / analysis
  • Deuterium / chemistry
  • Deuterium Exchange Measurement / methods*
  • Hydrogen / analysis
  • Hydrogen / chemistry
  • Metals, Alkali / analysis
  • Metals, Alkali / chemistry*
  • Molecular Structure
  • Spectrometry, Mass, Electrospray Ionization / methods*

Substances

  • Metals, Alkali
  • Hydrogen
  • Azithromycin
  • Deuterium